Transcript Slide 1

Liz Thomas
June 15, 2009
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Definition: Absence of airflow for at least 10
seconds despite persistence of respiratory
effort.
Severity of OSA can be classified based on the
apnea-hypopnea index (AHI, number of
apneas plus hypopneas per hour of sleep)
AHI 5-15 = mild
AHI 16-30 = moderate
AHI >30 = severe
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Obstructive sleep apnea
Inadequate sleep
Poor sleep hygiene
Chronic pain
Shift work
Medications
Drug, ETOH abuse
Depression
Insomnia
Limb movements
Narcolepsy
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Obesity
Craniofacial and upper airway anatomic
abnormalities (enlarged tonsils)
Increasing age
Untreated hypothyroidism
Male sex
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Excessive daytime sleepiness
Accounts by bed partner of witnessed apneas
and snoring
Awakening with sensation of gasping or
choking
Nocturnal diaphoresis
Morning headaches
Nocturia
Alterations in mood
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Requires nocturnal polysomnography
Includes electroencephalogram,
electrooculogram, chin electromyogram,
respiratory effort, airflow, pulse oximetry and
limb movements
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Conservative approach
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Weight loss
Exercise
Improved sleep hygiene
Supine preclusion
Nasal decongestants
Smoking cessation
Avoidance of sedating drugs
Avoidance of alcohol
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Nasal CPAP
Auto-CPAP
Bi-level ventilation
Oral appliances
Surgery: uvulopalatopharyhgoplasty, laser-assisted uvuloplasty,
improved nasal patency, maxillomandibular advancement
Definitive approach
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In patients with AHI >5 associated with
complaints of daytime sleepiness, CPAP
therapy has been shown to improve quality of
life, cognitive function, and symptoms of
daytime sleepiness. There are also beneficial
effects on mortality, blood pressure and
cardiac function.
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A 53-year old man is evaluated for management of OSA which
was diagnosed 2 months ago when he was evaluated for
excessive sleepiness. Polysomnography performed at that time
showed an apnea-hypopnea index of 55 events per hour. The
index normalized to 4 events per hour with CPAP at 18cm H2),
which was prescribed for his apnea.
He says now that he cannot tolerate nasal CPAP because of nasal
congestion and he has not used CPAP for two weeks. He has
continued daytime sleepiness that affects his performance at
work.
Which of the following is the most appropriate management for
this patient's condition at this time?
A) Refer for upper airway surgery for obstructive sleep apnea
B) Change to an auto-titrating positive airway pressure device
(APAP)
C) Prescribe an oral device to be worn during sleep
D) Manage nasal congestion and stress regular use of CPAP
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A 24 year old woman is evaluated for episodes of falling asleep
at inappropriate times during the day. Sleepiness occurs most
often after lunch or while driving a car. She goes to bed at
midnight and gets up for work at 6am. Her only medication is
oral contraceptives. She has no symptoms of depression, drug
use, restless leg syndrome, hypothyroidism, or insomnia. She
does not know whether she snores and no one in her family has
sleep problems. Physical examination reveals normal weight and
vital signs.
Which of the following is the most appropriate next step in the
management of this patient?
A) Schedule polysomnography
B) Counsel for proper sleep hygiene with increase in sleep time
C) Schedule electroencephalography
D) Prescribe modafinil
Type
PaO2/FiO2
CXR
Other
Acute Lung
Injury
<300
Bilateral
infiltrates
No CHF
Acute lung
failure
<300
Any infiltrates
No CHF
Acute
respiratory
distress
syndrome
<200
Bilateral
infiltrates
No CHF
Acute hypoxic
respiratory
failure
<200
Any finding
No COPD
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V/Q mismatch
Shunt
Diffusion abnormality
Decreased mixed venous oxygen
Greater acidity and higher temperature of
blood shift the oxyhemoglobin dissociation
curve to the right, lowering the blood oxygen
content for a given oxygen tension
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Pulmonary
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Acute bacterial or viral pneumonia
Gastric aspiration
Inhalation injury
Near drowning
Pulmonary contusion
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Severe sepsis
Hypertransfusion syndrome
Acute pancreatitis
Transfusion-related acute lung injury
Cardiopulmonary bypass
Non-pulmonary causes
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Failure of NPPV if patient is a candidate initially
Severe dyspnea with use of accessory muscles and
paradoxical abdominal motion
Respiration rate >35/min
Life-threatening hypoxemia (PaO2/FiO2 <200)
Severe acidosis (pH < 7.25) or hypercapnia (PaCo2
>60mm Hg)
Respiratory arrest
Impaired mental status
Cardiovascular complications (hypotension, shock,
heart failure)
Other complications (metabolic abnormalities, sepsis,
pneumonia, pulmonary embolism, barotrauma,
massive pleural effusion)
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Studied in ARMA trial
Showed reduction in ARDS mortality from 40% to 30% with a low
(6ml/kg) rather than high (12ml/kg) tidal volume
Established "lung protective" ventilator strategies to avoid
ventilator-associated lung injury resulting from excessive
stretching of the lung during mechanical ventilation
ALVEOLI study showed no advantage of a higher PEEP compared
to a lower PEEP, both adjusted to maintain adequate oxygenation
Current recommendation is to use either a volume- or pressurelimited mode with a low tidal volume (6ml/kg) while monitoring
plateau pressure that should be kept <30cm H2O.
PaCO2 is allowed to rise if necessary to achieve these goals
(permissive hypercapnea) and PEEP is adjusted to maintain FiO2
<60% with SaO2 >88%
If hypoxemia persists, prone positioning or high frequency
oscillation are sometimes used, but no studies have yet
demonstrated improved outcomes
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Avoid excessive minute volume that contributes
to dynamic hyperinflation (auto-PEEP) and
alkalemia that results from the compensatory
metabolic alkalosis for chornic hypercarbia
Keep tidal volume small (5-7ml/kg ideal body
weight)
Backup respiratory rate 10-14/min
Lower rate increases cycle time which permits
more time for exhalation and emptying of the
lung
Shortening Inspiratory time is another way to
increase expiratory time
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Invasive mechanical ventilation should be
avoided in patients with asthma if at all possible
Complications include pneumothorax and
pneumomediastinum
In needed, the approach is similar to that used
for COPD patients
Excessive respiratory rates and tidal volumes
should be avoided, plateau pressures should be
kept <30-35cm H2O and permissive
hypercapnea is used
When ventilation remains difficult, heliox or even
general anesthesia may be tried
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Minimizing the duration of mechanical ventilation
is desirable to reduce complications
When patients no longer require high levels of
oxygen (SaO2 >89% with FiO2 ≤40%), are
hemodynamically stable, and not excessively
sedated, spontaneous breathing trials using a Tpiece or low levels of CPAP or pressure support
should be initiated
If the patient tolerates SBP for 30-120 minutes
without excessive tachypnea, hemodynamic
instability, or oxygen desaturation, extubation
should be performed
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A 67-year old man is receiving mechanical ventilation for ARDS. He
underwent laparotomy and diverting colostomy for a ruptured
diverticulum 72 hours ago, and now has a fever to 40.0C and has diffuse
bilateral infiltrates that have been present for the past 1 day. Two deep
tracheal suction specimens are sent for culture and a gram stain shows
4+ gram negative rods. The patient’s oxygen saturation is worsening,
and his MAP has dropped to 58mm Hg despite three 1-L boluses of
normal saline, with only 15mL of urine output in the past hour. He is
also noted to have a lactic acidosis and thrombocytopenia, with a
platelet count now falling to 42,000 in the absence of heparin or H2antagonist therapy.
Which of the following would be appropriate management for this
patient?
A) Start resuscitation with colloids
B) Avoid activated protein C
C) Start low-dose dopamin
D) Adjust the ventilator with 6mL/kg of ideal body weight and a plateau
pressure <30cm H2O
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A 77-year old man on chronic hemodialysis is evaluated in the
emergency department for severe dyspnea. He is in respiratory distress,
but is alert and responsive. His blood pressure is 216/92, pulse 122, RR
44. He is using accessory muscles to breath. He has JVD; lungs have
bilateral crackles, and cardiac exam reveals a summation gallop with a
3/6 systolic murmur. There is no edema. ABG on 50% O2 by high-flow
mask are pO2 64, pCO2 50, pH 7.24. EKG shows sinus tach with nonspecific STT wave abnormalities and CXR is pending. He receives
oxygen, nitroglycerine, furosemide, and small doses of morphine but
remains very dyspneic.
Which of the following interventions would most likely avoid intubation
in this patient?
A) Increasing the dose of morphine; continue nitroglycerine and
furosemide
B) Starting noninvasive continuous airway pressure (4cm H2O)
C) Starting noninvasively administered pressure support (8cm H2O) and
PEEP (4cm H2O)
D) Increase the FiO2 via face mask
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A 78 year old man is admitted to the ICU from the ED where he had presented with a
respiratory arrest and was promptly intubated. The patient has a long history of smoking and
of severe COPD on long-term O2 therapy at home and a previous measurement of ABG’s on 2L
oxygen during a stable state revealed a pO2 of 92mm Hg, pCO2 58mmHg, and pH of 7.45.
Physical examination is notable for a barrel chest and fine expiratory wheezes. Heart sounds
are barely audible. ABG just before intubation were pO2 of 220mmHg, pCO2 of 122mmHg,
and pH of 7.04 while receiving 100% O2. In the ED , initial ventilator settings were
assist/control mode with a rate of 20/min, tidal volume of 600mL, PEEP of 5cm H2O and FiO2
of 50%. CXR shows hyperinflation, extensive bullous emphysema, and a RLL infiltrate.
On arrival to the ICU, he is hypotensive with a systolic pressure of 80mmHg, unresponsive to
an initial fluid bolus. A pulmonary artery catheter is inserted; right atrial pressure is 20cm
H2O, pulmonary artery pressure is 66/25 mmHg, pulmonary capillary wedge pressure is
21mmHg, and cardiac index is 1.8 L/min/m2. EKG shows a rate of 122/min, sinus rhythm
with multiple premature atrial beats, and nonspecific STT changes. During an accidental
disconnection from the ventilator, the patient’s blood pressure and wedge pressure normalize
but deteriorate when he is reconnected.
Which of the following is the most appropriate next step in the management of this patient?
A) Administer more fluids
B) Start dobutamine therapy
C) Obtain a repeat STAT portable chest radiograph
D) Lower the respiration rate and tidal volume
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Heterogeneous disorder that includes:
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Emphysema
Chronic Bronchitis
Obliterative Bronchiolitis
Asthma w/ bronchitis
GOLD: A disease states characterized by
airflow limitation that is not fully reversible.
Usually progressive and is associated with
abnormal inflammatory response
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Stage 0: Normal spirometry, chronic cough
and sputum production
Stage I: Mild FEV1/FVC <70% predicted and
FEV1 ≥ 80% predicted
Stage II: FEV1/FVC < 70% and FEV1 ≥ 50%
and < 80% predicted
Stage III: FEV1/FVC < 70% and FEV1 ≥ 30%
and < 50% predicted
Stage IV: FEV1/FVC < 70% and FEV1 < 30%
predicted or FEV1 < 50% predicted and
chronic respiratory symptoms
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GOLD - a report produced by NHLBI & WHO
defines COPD exacerbation as - acute
increase in sx beyond normal daily variation
Includes one or more of the following
cardinal symptoms (over 2 days):
◦ Cough increases in frequency and severity
◦ Sputum production increases in volume and/or
changes character
◦ Dyspnea increases
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It is estimated that:
◦ 50-60% COPD exacerbations are due to respiratory
infections
◦ 10% are due to environmental pollution
◦ 30% are of unknown etiology
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Most infection are thought to be viral, and
have been confirmed by viral culture or
serology in 18 - 64% of exacerbation
The most common viruses are influenza,
parainfluenza, coronavirus, and rhinovirus
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Viral infections cause the majority of COPD
exacerbations; bacterial infections also
trigger exacerbations
Most common bacterial causes:
◦ Haemophilus influenzae
◦ Moraxella catarrhalis
◦ Streptococcus pneumoniae
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Less Common include
◦ Kebsiella, Peduomonas
◦ Rarely - Chlamydia and Legionella
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Treatment of exacerbations of COPD includes
antibiotics directed against H. influenzae, M.
catarrhalis, and S. pneumoniae
◦ The use of antibiotics in exacerbations of COPD is
based on placebo-controlled trials that found
that antibiotics improve clinical outcomes in
many patients with an exacerbation of COPD
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Brochodilator, steroids, O2
"Standard"
Doxycycline
100 mg BID
Trimethoprim-sulfamethoxazole
DS BID
Amoxicillin
500 mg BID
"Modernized list"
Amoxicillin-clavulanate (Augmentin)
Azithromycin (Zithromax)
Cefpodoxime (Vantin)
Cefuroxime (Ceftin)
Cefprozil (Cefzil)
Loracarbef (Lorabid)
Levofloxacin (Levaquin)
Ciprofloxacin (Cipro)
875 mg BID
Z pack (6-250 mg)
200 mg BID
250-500 mg BID
500 mg BID
400 mg BID
500 mg QD
500 mg BID
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Stable COPD:
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Bronchodilaters
Anticholinergics
Steroids
(No mucolytics or leukotrienes)
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Bullectomy may reduce sx in pt w/ bulla
causing compression of adjoining lung tissue
-> improve lung function
Lung Volume Reduction surgery - FEV <20%
and diffusion capacity <20% and people with
upper lobe disease had better outcomes
Lung Transplant - FEV1 <35, PaO2 55-60,
PaCO2 >50
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A 72-year-old man is evaluated for progressive dyspnea on exertion and
a morning cough productive of thick white sputum. The patient is a lifelong cigarette smoker and was diagnosed with chronic obstructive
pulmonary disease 4 years ago; he has had two unscheduled office visits
in the past 6 months for bronchitis.
On physical examination, he is thin (BMI 20), his chest is hyperinflated,
breath sounds are diminished, he has 1+ ankle edema. Spirometry
shows an FEV1 35% of predicted which improves 5% with albuterol. Lung
volume measurement shows a total lung capacity of 140% and residual
volume of 130%; the DLco is 55% of predicted.
Which of the following is the most appropriate therapy for this patient?
(A) Albuterol, tiotropium, and inhaled corticosteroids
(B) Ipratropium bromide and tiotropium
(C) Albuterol/ipratropium bromide inhaler, a long-acting beta-agonist,
and oral corticosteroids
(D) Ipratropium bromide and montelukast
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A 45-year-old man is evaluated for mild dyspnea on
exertion. He has smoked 1.5 packs of cigarettes a day for
30 years. His personal and family medical history is
unremarkable.
On physical examination, the chest is clear; cardiac
examination and chest radiograph are normal. Spirometry
shows the FEV1 of 70%, FVC of 75%, FEV1/FVC of 70%.
After administration of a bronchodilator, the FEV1 rises to
80% and the FVC to 85%; the FEV1/FVC ratio is 75%. Ther
serum IgE concentration is normal, and there are no
eosinophils on the peripheral blood smear.
Which of the following is the most likely diagnosis?
(A) Chronic obstructive pulmonary disease, stage 0
(B) Chronic obstructive pulmonary disease, stage 1
(C) Moderate persistent asthma
(D) Restrictive lung disease